A survey of freshwater and terrestrial snails in a predominantly urban municipality of Rio de Janeiro State, Brazil, with emphasis on human parasites vectors

Abstract

Many snail species act as intermediate hosts of helminths that transmit diseases to humans and animals, such as schistosomiasis and angiostrongyliasis. São Gonçalo, a mostly urban municipality in Rio de Janeiro State, Brazil, has undergone fundamental environmental impacts, which favor the establishment of a range of diseases, for which snails act as the intermediate hosts of the etiological agents. In the present study, freshwater and terrestrial snail populations were surveyed in different environments within five city districts, and the presence of helminths was determined in the collected specimens. A total of 287 individuals were collected, six species from freshwater environment, Pomacea sp. (Ampullariidae), Melanoides tuberculata (Thiaridae), Biomphalaria tenagophila (Planorbidae), Dysopeas muibum (Subulinidae), Physa marmorata, and Physa acuta (Physidae), and two from terrestrial environment, Achatina fulica (Achatinidae) and Bradybaena similaris (Bradybaenidae). Snails were found in only two districts, Centro, an urban area, and Ipiiba, a rural area. Thirteen percent of the specimens of A. fulica eliminated larvae of the nematode Angiostrongylus cantonensis. None of the analyzed freshwater snails contained helminths.The most abundant and frequent snails were B. tenagophila, M. tuberculataand A. fulica, and the latter two species are exotic. The disturbance and degradation of natural areas adjacent to residential zones favor the proliferation of helminths, jeopardizing the local residents health. The abundance of A. fulica and B. tenagophila in the study area reinforces the need for a continuous and systematic monitoring of the snail fauna in this region.

The invasive giant African land snail,Achatina fulica(Gastropoda: Pulmonata): global geographical distribution of this species as host of nematodes of medical and veterinary importance

“…Angiostrongylus cantonensis has also been found in association with A. fulica on islands, such as the Hawaiian archipelago (Kim et al, 2014) and French Polynesia, in the Pacific Ocean (Fontanilla & Wade, 2012), Mayotte Island, in the Indian Ocean (Epelboin et al, 2016) and the Ilha Grande in Brazil (Oliveira & Santos, 2018), in the Atlantic Ocean. This nematode has also been recorded in Ecuador (Solórzano-Alava et al, 2019), Cuba (Meijides-Mejías & Robledo, 2019), Colombia (Giraldo et al, 2019), the contiguous United States, in Florida (Kwon et al, 2013;Rollins et al, 2021), Thailand (Dumidae et al, 2019;Jakkul et al, 2021), China (Lv et al, 2009), Japan (Matayoshi et al, 1987;Noda et al, 1987), Malaysia (Lim & Heyneman, 1965) and the Philippines (Tujan et al, 2016). In Europe, the single record from Italy was obtained from a study of snails being raised as pets, which evaluated the potential for the transmission of parasites from the animals to humans, and found snails infected with Rhabditis sp.…”

“…In a majority of the studies (50 papers), the nematodes were identified based on the analysis of their external morphology (table 1), with 13 of these studies employing experimental infection (Lim & Heyneman, 1965; Thiengo et al, 2010; Oliveira et al , 2015; Tomaz et al , 2018) and three, morphometry (Maldonado et al , 2010; Smith et al , 2015; Guerino et al , 2017). Molecular methods (polymerase chain reaction (PCR) and the sequencing of molecular markers) were also used ( n = 29 papers), in particular in Brazil (Caldeira et al , 2007; Thiengo et al , 2010; Carvalho et al , 2012; Guerino et al , 2017; Orico et al , 2019; Barbosa et al, 2020).…”

“…This technique involves the digestion of the A. fulica tissue in a solution of hydrochloric acid (HCl), with the resulting liquid being sedimented in a Baermann funnel for the isolation of the nematode larvae (Lim & Heyneman, 1965;Maldonado et al, 2010;Thiengo et al, 2010;Zanol et al, 2010;Rollins et al, 2021;Souza et al, 2021). Other methods were also used to extract the nematodes, including artificial digestion with pepsin (n = 19 studies), which was most frequent (n = 14) in Asia (Noda et al, 1987;Tujan et al, 2016;Lange et al, 2018;Penagos-Tabares et al, 2019;Jakkul et al, 2021). These two techniques, in a solution of HCl or pepsin were also more frequently used in South America, being significantly more used (P < 0.001) when compared to other methods.…”

“…The infected giant African land snails were collected principally in anthropogenic environments (both urban and rural), with specific characteristics, such as the front and back gardens of houses (peri-domestic environment), public parks, vacant lots and abandoned sites containing piles of trash and building rubble (Smith et al, 2015;Vázquez & Sánchez, 2015;Epelboin et al, 2016;Dard et al, 2017;Meijides-Mejías & Robledo, 2019;Pérez et al, 2019). Only a few studies (n = 7) refer to the capture of A. fulica specimens in the rural zone (Lim & Heyneman, 1965;Noda et al, 1987;Lv et al, 2009;Hu et al, 2011;Andrade-Porto et al, 2012;Tujan et al, 2016;Oda et al, 2020), where the snails were collected from plantations of rice (Oryza sp. ), rubber trees (Hevea brasiliensis (Willd.…”

A systematic literature review of schistosomiasis in urban and peri-urban settings

“…In particular, malacologic surveys appeared essential in understanding the prevalence of disease-relevant snail species, their infection levels, and changes in their distribution, with many of these studies having been carried out in Brazil [ 7 , 64 ]. The authors mentioned, for example, the disturbance and degradation of natural areas neighboring residential zones as responsible for the proliferation of molluscs.…”